1. Field of the Invention
The present invention relates to a document image filing system and in particular to a document image filing system having an input color mode selecting capability.
2. Description of the Related Art
Document image filing systems using optical disks are currently widely used as means of documentary management. The optical disks have a high capacity of storing data and are capable of recording a large quantity of image data. Accordingly, the optical disks are widely used as means for storing images of documents such as design drawings, contract documents and account books. If a document image is inputted into such a document image filing system, scanning operation is usually commenced after input mode information including paper size of a document to be inputted, line density, input density, designation information on whether the document is a character document or a half tone document has been set by an entry device such as an operation key provided on the scanner or a keyboard for document retrieval. The input image read by the scanner is displayed on a display screen. A user confirms the state of the document image on the display screen and determines whether or not the image is appropriate for registration on the file.
When a document image is registered in a file, it is necessary to confirm the input mode information such as paper size and line density which were preset for inputting the image as well as the picture quality of the document image which is actually inputted. Confirmation of the input mode has heretofore been made by confirming the state of the operation key of a scanner or a character array such as "A4. high definition" displayed in a given position of a display as is described at page 9 of an instruction manual for optical disk filing system of Hitachi Ltd. (Manual No. 2250-10-012-20).
Document image filing systems which are capable of storing color document images have recently been demanded to cope with the diversification of inputted document images. Generally, a color image requires the amount of data which is several to several ten times as much as that of a binary monochrome image. For example, if a document image is inputted in an RGB multivalued mode having 256 gradations, the amount of data would be 24 times as much as that in case where the document image is inputted in the binary monochrome mode. Accordingly, selection of a mode whether the inputted image is stored as a color data or a monochrome data gives a great influence upon the number of document images which can be stored in a memory medium such as optical disk.
A method of confirming the input mode based upon the state of the operation key of a color scanner or a character array such as "FULL COLOR MODE" displayed in a given position of a display has a high possibility of mistaking of the current input mode when confirmation whether an input image is appropriate or not is made prior to the registration of the document image.
If the last user of the filing system has inputted the image data in the full color mode in which a large capacity of memory is used, there is the possibility that the next user inputs document images in the previous input mode which has been preset by the previous user without changing the mode to an appropriate mode and registers them in a file. Even if the document to be inputted which is a monochrome document at this time is mistakingly inputted in the full color mode, the inputted image displayed on the display is, of course, a monochrome image. Accordingly the user who is devoted to the inputted image displayed on the screen after completing the scanning operation only checks whether or not the image has been scanned without skew when the inputted monochrome image is displayed on the screen. There is the possibility that he or she registers the image data in a file without noticing the wrong selection of the input color mode.